In court dockets, the pair call the atom smasher a "dark matter factory" that will spawn self-propelled bombs, "that is, substances, which actively attract and transform our normal matter and whose strength is such that once they become stable they cannot be controlled or destroyed by human beings.

"It is thus extremely dangerous to produce any quantities of strange matter or black holes on Earth."

Allowing the collider to proceed amounts to "global cultural genocide," the plaintiffs alleged.

The Hawaii court has not ruled on the case. The European Court of Human Rights rejected a similar case, brought by German chemist Otto Rössler, earlier this month.

One Hungry Golf Ball

To form black holes, the Large Hadron Collider would need to generate many billions of times more energy than it can, according to Jonathan Feng, a theoretical particle physicist at the University of California, Irvine.

And even if black holes formed, he said, they would be smaller than protons—which fit in the nuclei of atoms—and would evaporate in a miniscule fraction of a second, "long before they could grow by [absorbing] other matter," he wrote.

"Thus, even if black holes are produced at the LHC, they will not annihilate the Earth."

But Feng was willing to lay out his worst-case scenario, he said, "as long as we make it very clear we're going off the deep end."

If a black hole did form and begin eating Earth, there would be no spectacular display, Feng said.

"A committee of experts not on the LHC, including Nobel laureates, have said the findings are sound," Goldfarb said.

The collider experiments will mimic what has already happened a hundred thousand times when cosmic rays have bombarded Earth, Goldfarb said. If any of the feared possibilities were real risks, then continuous, natural cosmic ray assaults would have destroyed the planet long ago, he added.

In short, Goldfarb, who is based in France near the collider, isn't worried.

"My wife and two children live there," he said, "and they are not going to leave when we turn on the LHC."